So-called “crew-served” weapons are operated by one or two persons and generally include “light” machine guns, which fire non-explosive rounds, and “heavy” machine guns which fire larger rounds or grenades. For some weapons, such as grenade-launching machine guns, which fire relatively slow, heavy rounds, it is necessary to elevate the barrel relative to the sight line to the target for ballistics compensation at longer ranges. This relative upward tilt is known as “super-elevation” or “SEL.” The SEL tilt angle is variable depending on the range to the target and the size/weight of the rounds being fired, and may be relatively large, for example, up to about 30 degrees.
Conventional super-elevation devices operate based on mechanical adjustments between the weapon axis and the sighting device, setting the SEL angle prior to viewing and engaging the target. For example, referring to FIG. 1, the sighting device 110 may be mounted to the machine gun barrel 120 on an adjustable bracket 130. An operator estimates the range to a target, sets the bracket 130, for example, by adjusting the location of a set-pin 132 on bracket rails 134, to achieve a desired SEL angle 140, and then elevates the weapon. This mechanism has the disadvantage that the operator must then re-acquire the target using the sighting device 110 after the SEL angle 140 has been set.
U.S. Pat. No. 6,499,382 describes an electro-mechanical super-elevation device in which the sighting device can be disengaged from the weapon barrel and locked in position, such that the weapon may be elevated without moving the sighting device and thereby allowing the operator to continue to view the target through the sighting device during the super-elevation procedure.